The present invention relates generally to scrap crushing machines. More particularly, it relates to a scrap crushing machine which has crushing means including a hammer crusher rotor and an associated anvil, and a housing having inlet and outlet openings, a base extending under the rotor between the openings and the cover extending above the rotor between the openings, and also a separating device arranged at the outlet opening and a flap associated with the outlet opening as well.
Scrap crushing machines of the above mentioned general type are known in the art. One of such scrap machines is disclosed, for example,, in the German document DE-PS 3,643,529 corresponding to U.S. Pat. no. 4,146,184. In the housing of this scrap crushing machine, a separating edge of the flap which follows a screen wall of the base in direction of rotation of the rotor, deflects the scrap pieces which are not yet sufficiently crushed to a return chamber formed between the cover and the rotor so as to return them to the anvil. At the same time, it guides the scrap pieces which are not sufficiently crushed to the outlet of the machine, insofar as they enter channels formed between ribs of the separating device. The effective height of the ribs of the separating device can be changed either by swiveling the screen wall of the device relative to a rigidly arranged separating edge or by swiveling the separating edge relative to a rigidly arranged screen wall.
In the processing of scrap in the form of automobile bodies, or the like, it is often necessary to remove hard and/or large pieces of scrap from the housing while the rotor is running, in order to prevent damage to functional parts of the crushing machine. For this purpose in the above mentioned housing, it is known to support the screen wall in such a way that it can be swiveled around an axis arranged in the lower area, to an open position so as to open the outlet while the rotor is running. However, such a swivelable support is undesirable because of the high forces exerted by the scrap pieces, particularly on the lower portion of the screen wall. It also results in the scrap pieces impacting against the rigid separating edge in an uncontrolled manner when the screen wall is in the open position, which impedes a quick and complete removal of all scrap pieces located in the housing.